1. Field of the Invention
This invention relates to systems for coding and transmitting an image signal such as a television signal, and particularly to a system for making variable length coding of an image that is supplied as multi channel parallel data and contains a large amount of information, and then transmitting it in a multiplex manner at a specified speed.
2. Description of the Related Art
An example of the systems for coding and transmitting an image signal such as a television signal is disclosed in U.S. Pat. No. 4,920,426. In this example, single-channel data is subjected to variable length coding by the following process. The data is divided into blocks, an amount of information of each block is calculated, and the amount of codes generated from the data is estimated in advance. Then, a parameter (for example, quantization characteristic) for the control of coding is determined for each block in order that the result of coding matches the transmission speed on the transmission path.